eeprom_low.c

在AVR 平台下的控制代码,通过CAN控制

/**
 *  This code and information is part of Trident DPTV API (TDAPI)
 *
 *  Copyright (C) Trident Multimedia Technologies (Shanghai) Co., Ltd.
 *         2003  All rights reserved.
 *
 *  This file contains definitions and declarations related to EEPROM operations.
 *
 *  Revision:
 *  08/05/2003     Created by Archie
 *
 */

#include "std.h"
#include "I2C.h"
//#include "TEEPROM.h"                                                             

#define _TRY_TIMES_   5

static Byte s_ucSlaveAddr = 0xA0;



 
static Void tdEnableEEPROMI2C(Void)
{
    // disable WP here      
    tdI2COpen1();   
}

static Void tdDisableEEPROMI2C(Void)
{
    // enable WP here
    tdI2CClose1();
}

static Byte tdSendEEPROMStart(Word wSubAddress)
{
    Byte Loop = 0;
    tdStart();
    while (!tdI2CSendByte((Byte)(s_ucSlaveAddr & 0xfe)))
    {
        Byte Loop2;
        Loop++;
        if (Loop == 0xFF) return _FALSE_;
        for (Loop2 = 0; Loop2 < 0xFF; Loop2++)
        {
            Loop2--; Loop2++;
        }
        tdStart();
    }
    if (tdI2CSendByte((Byte)(wSubAddress >> 8)) && tdI2CSendByte((Byte)wSubAddress))
        return _TRUE_;
    return _FALSE_;
}

Void tdEEPROMWrite(Word wSubAddress, Byte * rpBuf, Word wLength)
{
    Word wLength2      = wLength;
    Byte * rpBuf2 = rpBuf;
    Byte ucTryTimes    = _TRY_TIMES_;
    Byte ucPageOffset;
     tdEnableEEPROMI2C();
    
    while (ucTryTimes--)
    {
        wLength  = wLength2;
        rpBuf    = rpBuf2;
        
        ucPageOffset = wSubAddress % 32;
        if(ucPageOffset != 0 && (ucPageOffset +  wLength > 32)) /* Across bonduary. Should write page twice */
        {
            if (tdSendEEPROMStart(wSubAddress))
            {
                while (ucPageOffset++ < 32)
                    if(!tdI2CSendByte(*rpBuf++)) goto quit;
                ucPageOffset = 32 - wSubAddress % 32;
                wSubAddress += ucPageOffset;
                wLength     -= ucPageOffset;
                tdStop();
            } else
                goto quit;
        }
        if (wLength > 32)
        {    
            while (wLength > 32)
            {
                Byte ucLen = 32;
                if (tdSendEEPROMStart(wSubAddress))
                {
                    while (ucLen--)
                        if(!tdI2CSendByte(*rpBuf++)) goto quit;
                    wLength     -= 32;
                    wSubAddress += 32;
                    tdStop();
                } else
                    goto quit;
            }
        }
        if (tdSendEEPROMStart(wSubAddress))
            while (wLength--)
                if(!tdI2CSendByte(*rpBuf++)) goto quit;
                
quit:
        tdStop();
        if (wLength == 0xFFFF)
            break;
    }
    
    tdDisableEEPROMI2C();
}

Void tdEEPROMRead(Word wSubAddress, Byte * gpBuf, Word wLength)
{
    Word wLength2     = wLength;
    Byte * gpBuf2 = gpBuf;
    Byte ucTryTimes    = _TRY_TIMES_;
 
    tdEnableEEPROMI2C();

    while (ucTryTimes--)
    {
        wLength  = wLength2;
        gpBuf    = gpBuf2;
        if (tdSendEEPROMStart(wSubAddress))
        {
            tdStart();
            if(tdI2CSendByte((Byte)(s_ucSlaveAddr | 0x01)))
            {
                while (wLength)
                {
                    *gpBuf++ = tdI2CReceiveByte();
                    /*send ACK*/
                    if(--wLength)
                        tdACK();
                }
                /*send No ACK*/
                tdNOACK();
                tdStop();
                break;
            } 
        }
        
        tdStop();
    }
    tdDisableEEPROMI2C();
 }

Void tdEEPROMWriteByte(Word wSubAddress, Byte ucValue)
{
    Byte ucTryTimes    = _TRY_TIMES_;
      tdEnableEEPROMI2C();

    while (ucTryTimes--)
    {
        if (tdSendEEPROMStart(wSubAddress))
            if (tdI2CSendByte(ucValue))
            {
                tdStop();
                break;
            }
        tdStop();
    }

    tdDisableEEPROMI2C();
 }

Byte tdEEPROMReadByte(Word wSubAddress)
{
    Byte ucTryTimes = _TRY_TIMES_;
    Byte ucValue    = 0xFF;

    tdEnableEEPROMI2C();

    while (ucTryTimes--)
    {
        if (tdSendEEPROMStart(wSubAddress))
        {
            tdStart();
            if(tdI2CSendByte((Byte)(s_ucSlaveAddr | 0x01)))
            {
                ucValue = tdI2CReceiveByte();
                /*send No ACK*/
                tdNOACK();
                tdStop();
                break;
            }
        }
        tdStop();
    }

    tdDisableEEPROMI2C();
    return ucValue;
}

/* set device address and check if the device is onling */
Bool tdEEPROMSelectDevice(Byte ucDeviceAddress)
{
	Byte ucTryTimes = _TRY_TIMES_;
    s_ucSlaveAddr = ucDeviceAddress;
	tdEnableEEPROMI2C();

	while (ucTryTimes--)
	{
		if (tdSendEEPROMStart(0x0000))
		{
			tdStop();
			break;   // OK, return;
		}
		tdStop();
		// wrong, try again
	}
		
	tdDisableEEPROMI2C();
	return ucTryTimes != 0xFF;

}